This invention is a type of flux switch alternator. A flux switch alternator, as conventionally constructed, comprises a pair of stationary magnets and a pair of pole pieces joining the like poles of the magnets. The magnets and pole pieces are shaped into a circular stator configuration surrounding a concentrically mounted rotor of high permeability material. An inwardly directed salient member is formed at each end of both pole pieces and the rotor is formed with outwardly directed teeth similar to those of a gear. Conductor coils are wound upon each pole piece between the salient end members thereof. The width of each rotor tooth and the spacing between rotor teeth is substantially equal to the width of a pole piece salient. The teeth are of such height that when a rotor tooth is aligned with a pole piece salient only a very short radial air gap exists therebetween. When a rotor tooth space is aligned with a pole piece salient, a much longer radial air gap exists between the pole piece salient and the rotor body. The pole piece lengths, the width of the pole piece salients, the rotor tooth width and rotor tooth spacing are all so selected that when a rotor tooth underlies the upper salient of one of the pole pieces a different rotor tooth underlies the lower salient on the other pole piece. Simultaneously, the lower salient of the one pole piece and the upper salient of the other pole piece each overlies a different one of the rotor tooth spaces. Rotation of the rotor by an amount equal to one rotor tooth width causes the relationships between salients and rotor teeth and between salients and tooth spacings to be interchanged. Then the upper salient of the one pole piece and the lower salient of the other pole piece rotor overlie tooth spaces, while rotor teeth underlie the lower salient of the one pole piece and the upper salient of the other pole piece.
When the rotor is in the first position described, magnetic flux from one of the magnets will thread the coil on the one pole piece in one direction, while the magnetic flux from the other magnet threads the coil on the other pole piece in the opposite direction. When the rotor is in the second position described, the magnetic sources of the fluxes threading the coils are interchanged between the magnets and the direction of the fluxes through the coils are reversed. These changes in magnetic sources and flux directions through the coils induce alternating potentials in each of the coils.
In the present invention the stator elements of the flux switch alternator described are arranged in a linear configuration. The linear stator arrangement is adapted for mounting adjacent a large ring gear or rack gear which is an integral part of a large prime mover, such as a stationary industrial engine used in a pumping station. The engine gear then serves as the rotor element of the alternator.
A primary advantage of the invention is that it is readily adaptable for retrofit installation in large engines merely by the provision of a suitable mounting bracket near the tooth surface of an existing engine gear.
Another advantage of the invention is that it can be designed to provide sufficient output capacity to power the electronic circuits of an electronic ignition system for the engine to which it is fitted, thereby eliminating the need for a battery and charging system.
Still another advantage of the invention, as compared to rotating electric generators, is that it can be fitted to an engine without the necessity for the provision of a rotary auxiliary drive, such as a belt, gear or shaft coupling system.